Transmission of mutans streptococci in mother-child pairs.

BACKGROUND & OBJECTIVES: Dental caries is an infectious, transmissible disease. Maternal transfer of mutans streptococci (MS) has been a subject of research. The aim of this study was to evaluate the transmission of MS from mother to children through genetic analysis. METHODS: Thirty mother-child pairs were included and divided into three groups according to the age of the children. Saliva samples were collected and MS colonies from each mother-child pair were isolated. After inoculation and incubation, MS colonies were submitted to amplification technique by polymerase chain reaction (PCR) for identification and arbitrarily primed PCRs (AP-PCRs) to determine various MS genotypes. RESULTS: From birth to six months of age, 30 per cent of children exhibited MS colonization, and by the age of 30 months, 100 per cent harboured the bacteria (P < 0.001). Factors associated with MS colonization were eruption of teeth (P < 0.001), feeding habits with mean colony count being significantly lower in breast-fed as compared to bottle-fed children (P < 0.001) and a significant association between mean MS count of child and mother's practice of sharing spoon with child (P < 0.001). The AP-PCR fingerprinting profile analysis showed 17 MS groups (clusters) containing identical or highly related isolates in mother-child pairs with a high level of similarity (77.27 %). INTERPRETATION & CONCLUSIONS: The presence of matching MS genotypes suggested vertical transmission from mothers to children. Feeding habits, gum cleaning and number of erupted teeth in children had significant effect on MS colonization. There is a need to develop strategies to present MS colonization in children.

Clinical and radiographic assessment of mineral trioxide aggregate and calcium hydroxide as apexification agents in traumatized young permanent anterior teeth: A comparative study.

BACKGROUND: To evaluate and compare the efficacy of mineral trioxide aggregate (MTA) and traditionally used calcium hydroxide (Ca(OH)2) in inducing root end formation of immature roots of traumatized young permanent anterior teeth. MATERIALS AND METHODS: The study was carried out on 22 nonvital, immature permanent maxillary incisors. Samples were allotted into two groups - Group I MTA and Group II Ca(OH)2 Success rate was determined based upon the time duration required for apical barrier formation. The canals were obturated using gutta-percha points in MTA group, after 24 h, whereas in Ca(OH)2 group, obturation was carried out after radiographic confirmation of the apical barrier. The clinical and radiographic evaluation was carried out at a follow-up periods of 3, 6, and 9 months and statistical analysis was carried out by SPSS version 15.0 statistical analysis software (Chi-square test and fisher exact test). RESULTS: In MTA Group, barrier formation was observed in 90.90% of the patients after 9 months whereas in Ca(OH)2 Group, the same was observed in 81.81%. The mean time required for barrier formation in MTA group was 4.90 months and 5.33 months in Ca(OH)2 group. CONCLUSION: MTA and Ca(OH)2, as medicaments for apexification, were comparable in terms of the evaluation parameters. However, MTA was beneficial in terms of immediate obturation of immature roots with wide open apices.

Correlation between dental caries experience and mutans streptococci counts by microbial and molecular (polymerase chain reaction) assay using saliva as microbial risk indicator.

BACKGROUND: The aim of this study was to assess the relationships of quantitative salivary levels of mutans streptococci (MS) in children, aged 3-6 years and 12-15 years, exhibiting variable patterns of caries activity, and to compare the association of MS in saliva using microbial and molecular (polymerase chain reaction [PCR]) assay. MATERIALS AND METHODS: In this cross-sectional observational study, eighty children were included, forty children each in Group I (3-6 years) and Group II (12-15 years). Children were further divided into two subgroups (Group IC, INC and Group IIC, IINC) based on their dental caries status. Saliva samples were collected and plated onto Mitis Salivarius-Bacitracin agar plates. After detection of MS, DNA was isolated and purified, and MS were evaluated using the PCR and AP-PCR. RESULTS: Of the selected 80 children, 42 were male and 38 were female. In Group IC, the mean colony count was 2.27 ± 0.54 × 105 CFU/ml, and in Group INC, the mean colony was found to be 1.61 ± 0.54 × 105 CFU/ml. In Group II, where mean colony count of 3.31 ± 0.85 × 105 CFU/ml and 2.44 ± 0.54 × 105 CFU/ml was observed in Group IIC and Group IINC, respectively. CONCLUSION: The mean colony count increased with increasing age and was also more in children with dental caries. Based on the matrices generated by the PCR analysis using coefficient slipped-strand mispairing, wide range of genetic diversity was seen in cases of children with and without clinically detectable caries.